Purpose: To quantify changes of bone marrow microcirculation in multiple myeloma (MM) using contrast enhanced dynamic MRI (dMRI) during thalidomide as antiangiogenic monotherapy or in combination with chemotherapy (cyclophosphamide, etoposide, dexamethasone).
Materials and methods: The study includes 63 patients with refractory or relapsed MM, who underwent dMRI with high temporal resolution (T1w-turboFLASH) of the lumbar spine before and following treatment. The contrast uptake was quantified using a two compartment model with the output parameters amplitude and k (ep) (exchange rate constant). The evaluation considered the initial dMRI finding (pathological or non-pathological) and the clinical therapeutic response (response or no response).
Results: During monotherapy with thalidomide (n = 38), no significant changes of the dMRI parameters were found, even when considering the initial dMRI finding (positive n = 22) and the therapeutic response (responder n = 14). The combination with chemotherapy (n = 25) had a significant reduction of k (ep) (p = 0.01) in 18 patients with positive initial dMRI finding and therapeutic response. Reduction of the amplitude was seen in most cases, but in the end without any significance (p = 0.09).
Conclusion: dMRI can quantify significant changes of bone marrow microcirculation solely during treatment with thalidomide combined with chemotherapy, not with thalidomide alone.